Sea-Level Rise and Shoreline Changes Along an Open Sandy Coast: Case Study of Gulf of Taranto, Italy

Abstract

The dynamics of the sandy coast between Castellaneta and Taranto (Southern Italy) has been influenced by many natural and anthropogenic factors, resulting in significant changes in the coastal system over the last century. The interactions between vertical components of sea-level changes and horizontal components of the sedimentary budget, in combination with anthropogenic impact, have resulted in different erosion and accretion phases in the past years. Local isostatic, eustatic, and vertical tectonic movements, together with sedimentary budget changes, must be considered in order to predict the shoreline evolution and future marine submersion. In this study, all morpho-topographic data available for the Gulf of Taranto, in combination with Vertical Land Movements and sea-level rise trends, were considered by assessing the local evolution of the coastal trend as well as the future marine submersion. Based on the predicted spatial and temporal coastal changes, a new predictive model of submersion was developed to support coastal management in sea-level rise conditions over the next decades. After that, a multi-temporal mathematical model of coastal submersion was implemented in a Matlab environment. Finally, the effects of the relative sea-level rise on the coastal surface prone to submersion, according to the Intergovernmental Panel on Climate Change Assessment Reports (AR) 5 Representative Concentration Pathways (RCP) 2.6 and RCP 8.5 scenarios, were evaluated up to 2100.

Relative Sea-Level Rise Scenario for 2100 along the Coast of South Eastern Sicily (Italy) by InSAR Data, Satellite Images and High-Resolution Topography

“…The analysed area also experienced the effects of several storms and Medicanes occurred over the last decades, mainly represented by boulders dislocation along the coastal area [19]. This is particularly important considering that in a SLR scenario the effects of the extreme marine events will probably impact on the coastal landscapes currently emerged [31,32,68,[77][78][79][80].…”

“…The analytical expression that we applied to calculate vertical and eastwest motions is reported in Dalla Via [99]. Generally, ground movements along the coastal stripes are characterized by subsidence phenomena due to the coastal erosion and soil compaction causing as a consequence the retreat of the coastline [80,100,101]. Moreover, the tectonic regime of the area of interest foresees vertical movements, e.g., rise of marine terraces [58,60,62,65].…”

“…We used the time series of optical satellite images Landsat 7-8 [105] acquired in the time span 2001-2019 and multispectral WorldView 2 acquired in 2011 to evaluate the horizontal migration of the sandy shorelines that underwent to significant retreat. The effective shoreline migration was obtained following the method described in Scardino et al [80]. From all the selected images, the shorelines were digitalized in GIS environment for each year reported in the satellite images.…”

Monitoring the Coastal Changes of the Po River Delta (Northern Italy) since 1911 Using Archival Cartography, Multi-Temporal Aerial Photogrammetry and LiDAR Data: Implications for Coastline Changes in 2100 A.D.

“…The DTMs obtained from the LiDAR surveys can be used to perform a prevision of the emerged surfaces outside to the levees in 2100, taking into account SLR and land subsidence values in the analyzed area projected to 2100 [47][48][49]. These phenomena, which proceed in opposite directions, (i) increase the flooding risks of the PRD due to the decrease in the safety margin between the top of the levees and the mean sea level and (ii) could increase the levees instability due to the reduction of the sandy cords (emerged surfaces) that protect themselves from the erosive action by the sea waves motion.…”

Protecting Coastlines from Flooding in a Changing Climate: A Preliminary Experimental Study to Investigate a Sustainable Approach

“…In the last 140 years, scientific research has established that average sea levels have significantly increased [1][2][3], and this phenomenon is accelerating. This is a critical issue as even small increases can have devastating effects on coastal habitats [4][5][6][7].…”